Self-cleaning spark plug



May 12, 1925.

A. CHAMPION SELF CLEANING SPARK PLUG Filed Oct. 28, 1922 [5 m 7 mm H0 mmPatented May v 12, 1925.

UNITED STATES ALBERT CHAMPION, OF FLINT, MICHIGAN, ASSIGNOR TO A. CSPARK PLUG COM- PANY, 0F FLINT, MICHIGAN, CORPORATION OF MICHIGAN.

SELF-CLEANING SPARK PLUG.

Application filed October 28, i922. Serial No. 597,611.

T 0 all whom it may concern:

'Be it known that I, ALBERT CHAMPION, a citizen of the Republic ofFrance and a resident of Flint, county of Genesee, and

State of Michigan, have invented certain new and useful Improvements inSelf-Cleaning Spark Plugs, of which the following is a full, clear,concise, and exact description,

such as will enable others skilled in the artprovlde an improved sparkplug having a construction of grounded or shell electrode such that theliability to short circuit will be reduced to a minimum, such end being,attained by providing a grounded or shell electrode of such form andwhich is so arranged relative to the central insulated electrode thatsuch oil or other liquid as may accumulate thereupon will run down andaway from the spark gap of the plug, thus maintaining the same in aclean condition at all times.

In internal combustion engines, especially such as are designed tooperate u 11 comparatively heavy hydrocarbons, t ere is a decidedtendency .of the fuel used to condense within the cylinder andaccumulate upon the spark plug and other internal parts of the cylinder;which condensate, should it accumulate to any considerable extentbetween the electrodes of the plu will result inshort circuiting thesamean in preventing the engine from operating. In my improved sparkplug, however, the stationary or shell electrode is of such form and isso arranged that such condensed fuel as may accumulate at the spark gapwill naturally run down and away therefrom and fall from the shellelectrode, thus maintaining the gap I always open and preventing shortcircuitmg of the plug.

The idea of invention above expressed ma be carried out in many ways,two of whlch are illustrated in the drawing accompanying and forming aart ofthis specification; although it will e appreciated that myinvention includes such other specific of Figure l.

-tionary or shell electrode.

forms of stationary electrode as come" within the scope of theconcluding claims wherein the distinguishing features of my inventionare particularly pointed out.

Referring now to the drawing: v Figure 1 is a view showing a sectionupon a vertical central plane of a spark plug having a grounded or shellelectrode made in accordance with my invention. Figure 2 1s a nowshowing 1n Flgure 1 as seen the same. I

the In shown from 'a position eneath Figure 3 is a fragmentary viewshowing the plug as seen from a position at the left Fi re l showing aslightly modified form of sta- Figure 5 is 51. view showing the plushown in Figure l as seen from a position neath the same.

Figure 6 is a view at .the lower end of the plug shown in Figure 4 asseen from a'position to the left thereof.

In the drawing, the reference numeral 10 designates the exteriormetallic shell or casis a view similar to Figure 1, but

ing of a spark plug, the same being hollow and adapted to receive theinsulating member 11; said insulating member being held in place withinthe casing by an inturned holding flange 12, as is usual in spark plugsof the single iece variety or type. It W111 be appreciate however, thatmy invention is in no way limited in the manner in which the insulatingmember is held in place wlthin the casin and is equally applicable tovplugs wherein said member is ty es of ar p Sp and is held thereremovablefrom the casing, in by a suitable gland nut.

Extending through the insulating memher is the usual central electrode13 of the plug; and the reference 14=- designates the grounded or shellelectrode. trode extends, as shown in the drawing downward some littledistance below the lower extremity of the central electrode and is bentat right angles, and extends inward and terminates in a position beneaththe power end of the central electrode;'the bent portion indicated bythe reference numeral 15 lying below the level of the spark ga betweenthe extremities of the centralan shell electrodes.

The laterally extending portion of the I l shell electrode is preferablyso shaped as to This shell elecprovide downwardly diverging sides orwalls 16, 17, which merge with one another alon the upper edge 18 of thehorizontal portion to thereby provide a sharp ridge,

- as best shown in Figures 2 and 3. The'apex of the horizontal portionat the extremity thereof lies beneath andprovides a comparatively.sharpvedge opposite the lower end of the insulated electrode; from whichit follows that when the plug is in use such liquid as may accumulateupon-the grounded electrode due to condensation of the fuel employed orof oil supplied for lubricating purposes will run down the inclinedsides 16, 17 and drip from the lower edges there of;rit being understoodthat the plug will ordinarily be used in a vertical position like thatin which it is illustrated. This running down of the condensed liquidwill precventthe accumulation'of the same at the spark gap and preventshort circuiting of t the result being that the-spark e plu iept free atall times from'liquid gap is which. would otherwise tend to foul andshort circuit the same. a I

In the'form' of my invention shown in Figures 4, 5 and 6 theconstruction of the insulator, the central electrode and the externalshell or casin is substantially the same as hereinbe ore described. The

grounded or shell electrode, howeveF, is of somewhat different form; thesame comprising a depending portion 19, a substantially horizontalortion 20 extending to a .position beneat the central electrode, and anupwardly bent extremity 21 which lies beneath and opposite the lower endof the central electrode. It will be seen that this central portion 20is disposed below the .level of the spark gap so that such oil asmayaccumulate upon the shell electrode will run down onto the,horizontal part 20 and drip therefrom without accumulating at the sparkgap thus keeping the spark gap free from condensedoil or hydrocarbon andpreventing short-circuitingIof the plug in substantially the same manneras hereinbefore explained. 1

Having thus described'and explained my invention, I claim and desire tosecure by Letters Patent:

1. In a spark plug the combination with a central insulated electrode,of a grounded or shell electrode having angangularly bent portion withdiverging sides extending throughout substantially -.the whole length ofsaid. portion, said angularly bent portion being located beneath'thecentral electrode and arranged with its apex upward, so that such oil asmay condense upon the same run down and drip from the lower may edges ofthe sides of said angularly bent portion. x

2. In a spark plug the combination with a central insulated electrode,of a grounded or shell electrode havinga vertical portion extendingdownwardfrom the shell, and a ho rizontal portion extending'from saidverbetween the extremities of the electrodes and the fouling of theplug.

' In testimony whereof I afiix my signature.

ALBERT CHAMPION.

